But in the end of October he was attacked by a bilious disorder, which, increasing in severity, rendered him, early in November, incapable of attending to business. It is, indeed, surprising that this attack should have been so long delayed. From the moment he arrived in Bengal, his mind had been kept invariably on the stretch, by a succession of painful and trying exertions. He had travelled much in the midst of the monsoon, and in the hottest season. On one occasion, he writes to Mr. Verelst[111], "I have not had three hours' sleep any day or night, since I left Mootyjil," a fortnight before; and, even during the period when he thus travelled in a burning climate[112], he continued anxiously corresponding at every interval of his journey, on the subject of an alarming mutiny, which threatened destruction to all his plans of public improvement. He had difficulties to encounter on every side, reforms to be made, in which he was obliged to depend for success, more on the energy of his own mind, than on the support of the service, or of his coadjutors. He had the ungracious office of interfering at every step with the pecuniary emoluments of the majority of his countrymen of every class. Few constitutions could have supported the anxiety he endured. A less vigorous mind would have sunk under the fret and annoyance of nearly two years' warfare of this exhausting kind: his constitution only sank under the fatigue. The strongest proof how severe his illness became, is afforded by the total interruption of his correspondence from the 29th of November to the 27th of December, during which period no letter appears to have been written by himself, the correspondence being entirely conducted in his name by Mr. Strachey. It has already been remarked that his regularity and constancy in correspondence were quite exemplary. His letters of business were answered the moment they were received. This steady regularity, too often despised by inferior men, was one of the means by which he did so much. With him it was grown into a habit; but the habit was a proof of the energy of a mind eager to accomplish, in the most perfect way, the business in which it is engaged.